Confirmation that the government-funded school lunch programme is under review has sparked serious concern from health charities and principals.

The programme, Ka Ora, Ka Ako, was introduced by the Labour government in 2019. It now provides free healthy lunches to more than 220,000 students - about a quarter of all students.

But Associate Education Minister David Seymour said 10,000 lunches were wasted each day and there was no hard evidence the programme, which cost about $325 million annually, improved school attendance or achievement.

On Monday, he told Checkpoint he was looking to cut funding for the programme by up to half.

Health Coalition Aotearoa has asked Seymour for a meeting about the programme to try to ensure its future.

In an interview with Nine to Noon, co-chairperson Professor Boyd Swinburn acknowledged that a report by Treasury, put out last year in the lead-up to the Budget, did not find evidence of improved achievement or attendance at schools receiving the lunches.

▶ LISTEN "You can imagine trying to learn maths when your stomach is grumbling" - Boyd Swinburn

However, studies had shown the programme had other benefits for students, such as improved mental health and wellbeing, he said.

It also found the programme improved nutrition for 7.3 percent of students, who did not have sufficient access to food at home.

Swinburn said Seymour should not "flip it off and say, 'because it's not meeting one of these [measures], then we need to ditch the programme".

There was a "suite" of evidence he and other public health advocates wanted to put in front of the minister, he said.

Professor Boyd Swinburn. Photo: Supplied

"We need to remember that a lot of these kids have poor nutrition, we have very high obesity, we have 35 percent of Māori kids living in households that have food insecurity, and this is definitely a benefit for whānau resources when it comes to trying to pay for the expenses of food."

According to results from the Programme for International Student Assessment (Pisa) - a worldwide study looking at 15-year-olds' achievement - students living with food insecurity were, on average, two to four years behind their schoolmates, Swinburn said.

"You can imagine trying to learn maths when your stomach is grumbling because you haven't had breakfast and you haven't had lunch."

Dr Pippa McKelvie-Sebileau has been researching the effectiveness of the programme, particularly in Hawke's Bay.

She said the difference in achievement when students missed meals was "pretty stark", even accounting for other factors associated with hunger, like socioeconomic deprivation.

▶ LISTEN "Students who are missing meals up to every day are four years behind in their learning" - Dr Pippa McKelvie Sebileau duration

As well as the Pisa study, data from the Trends in International Maths and Science study showed "the same enormous differences" in achievement between students with enough food and those who went hungry, McKelvie-Sebileau said.

While the Treasury study did not show an improvement in attendance in students receiving free school lunches, it was carried out in 2021 "during a really bizarre time" - the aftermath of the Covid-19 lockdowns, when "it was really hard to get students into schools", she said.

Cutting the programme would make it incredibly difficult for some whānau to make ends meet, McKelvie-Sebileau said.

"The cost of food has increased, the cost of living has increased and to add that to their family bill would really be a tragedy."

'Not necessarily' fewer children, schools getting lunches - Luxon

Prime Minister Christopher Luxon said the review of the programme did "not necessarily" mean fewer children or schools would receive the free lunches.

National promised during the election campaign to continue the programme, but with some changes to make it more efficient.

"Our coalition agreement's really clear, we are supporters of the school lunch programme - but like every programme across this country, and government, we are very determined to make sure that we can make it more efficient, more effective and make sure there's less waste," Luxon said at the weekly post-Cabinet media briefing.

"What it means is, look, the school lunch programme has been in place, we had a Labour government that was going to stop funding it on January 2025 - end of story, there's no money going into school lunches beyond January 2025.

"We believe in the programme. We are now funding the programme, but we want to make sure that it's been effective. That's quite a good question to ask a few years down the road as the programme's got bigger and as we have made a big commitment to fund it - to make sure we're getting a return on it."

The previous Labour government discontinued funding for the programme from the end of this year, but confirmed during the election campaign it would continue to fund it at the current settings.

Principal warns school will have to buy lunches for kids if programme axed

Westport South School principal Craig Adams told Midday Report the lunch programme "enables success for our students".

He was alarmed at news it was under review. Before it began, "some students were just not having a school lunch", he said.

▶ LISTEN "Families are really struggling at the moment" - Craig Adams 

"We would constantly have to be buying and supplying school lunches out of our operating grant, which takes away from other initiatives that we need to pay for in school.

"For some people, who can't afford [groceries], school lunches are a real lifeline."

About 230 children, or 80 percent of the students at Westport South School, received lunches through the programme.

Adams said he could not speak to the wider issue of wasted lunches, but said company that supplied his school also supplied another in the area, which had a later lunch break.

Any lunches not eaten at Westport South were then taken to the other school, so wastage was minimal, he said.

"Our process is pretty streamlined."

Associate Education Minister David Seymour. Photo: RNZ / Samuel Rillstone

Seymour told Nine to Noon he took the issue of free school lunches "extremely seriously".

He said the government was in a "difficult position", as the previous government had committed to the spending programme "without commissioning any robust empirical study to evaluate its effectiveness".

"What's worse, the evidence that is in place indicates that the free school lunch programme has not improved attendance or achievement in any measurable way," he said.

"I will be looking at what evidence we do have, and what feedback we get from the community, in order to make a decision that balances the country's books and the expectations people have around the free school lunch programme."

Seymour told Checkpoint there was agreement among all three parties in the coalition government that a programme offering taxpayer-funded school lunches would continue in "some form".

What exactly that would look like was still up for discussion, he said.

He was looking to cut its funding by between 30 and 50 percent - a government saving of between $100m and $160m - but did not want to name an exact figure while he was still receiving advice on the programme, he said.

To make those savings, either the number of schools or students receiving the lunches could be cut, or the programme itself could be changed.

'It's making a real difference'

But a Porirua Principal said free lunch in schools was the most successful education initiative she had ever seen rolled out.

Porirua College feeds more than 1000 students a day across the city under the scheme.

Principal Ragne Maxwell said she was deeply disappointed the government wanted to reduce funding.

"It's making a real difference for young people and their ability to learn, attend school and succeed with their work. Removing any support from it is going to cut back on the effectiveness of the programme or the number of people it's trying to reach."

Maxwell said if the government wanted to eliminate wasteful spending it should equip more schools to deliver free lunches themselves.

She said the coalition could free up funds by cutting the profit margin for businesses providing lunches.

"We cook the lunches ourselves in our school, obviously we're not making any profit from the situation. Now not all schools have those facilities but where you can set up schools to be able to deliver without there being any question of profit being put in anyone's pocket, that's where I think you'll get the really targeted, effective use of money."

Maxwell said feeding kids at school was having a direct effect on learning outcomes.

This story was originally published by RNZ